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Author Sevik, C.; Wallbank, J.R.; Gulseren, O.; Peeters, F.M.; Çakir, D.
  Title Gate induced monolayer behavior in twisted bilayer black phosphorus Type A1 Journal article
  Year 2017 Publication 2D materials Abbreviated Journal 2D Mater
  Volume 4 Issue 3 Pages 035025
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Optical and electronic properties of black phosphorus strongly depend on the number of layers and type of stacking. Using first-principles calculations within the framework of density functional theory, we investigate the electronic properties of bilayer black phosphorus with an interlayer twist angle of 90 degrees. These calculations are complemented with a simple (k) over right arrow . (p) over right arrow model which is able to capture most of the low energy features and is valid for arbitrary twist angles. The electronic spectrum of 90 degrees twisted bilayer black phosphorus is found to be x-y isotropic in contrast to the monolayer. However x-y anisotropy, and a partial return to monolayer-like behavior, particularly in the valence band, can be induced by an external out-of-plane electric field. Moreover, the preferred hole effective mass can be rotated by 90 degrees simply by changing the direction of the applied electric field. In particular, a +0.4 (-0.4) V angstrom(1) out-of-plane electric field results in a similar to 60% increase in the hole effective mass along the y (x) axis and enhances the m(y)*/m(x)* (m(x)*/m(y)*) ratio as much as by a factor of 40. Our DFT and (k) over right arrow . (p) over right arrow simulations clearly indicate that the twist angle in combination with an appropriate gate voltage is a novel way to tune the electronic and optical properties of bilayer phosphorus and it gives us a new degree of freedom to engineer the properties of black phosphorus based devices.
  Address
  Corporate Author Thesis
  Publisher IOP Publishing Place of Publication Bristol Editor
  Language Wos 000406926600001 Publication Date 2017-08-03
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.937 Times cited 13 Open Access
  Notes (down) ; This work was supported by the bilateral project between the The Scientific and Technological Research Council of Turkey (TUBITAK) and FWO-Flanders, Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. We acknowledge the support from TUBITAK (Grant No. 115F024), ERC Synergy grant Hetero2D and the EU Graphene Flagship Project. We also thank Vladimir Fal'ko for helpful discussions. ; Approved Most recent IF: 6.937
  Call Number UA @ lucian @ c:irua:145151 Serial 4717
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Author Aierken, Y.; Sevik, C.; Gulseren, O.; Peeters, F.M.; Çakir, D.
  Title MXenes/graphene heterostructures for Li battery applications : a first principles study Type A1 Journal article
  Year 2018 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A
  Volume 6 Issue 5 Pages 2337-2345
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract MXenes are the newest class of two-dimensional (2D) materials, and they offer great potential in a wide range of applications including electronic devices, sensors, and thermoelectric and energy storage materials. In this work, we combined the outstanding electrical conductivity, that is essential for battery applications, of graphene with MXene monolayers (M2CX2 where M = Sc, Ti, V and X = OH, O) to explore its potential in Li battery applications. Through first principles calculations, we determined the stable stacking configurations of M2CX2/graphene bilayer heterostructures and their Li atom intercalation by calculating the Li binding energy, diffusion barrier and voltage. We found that: (1) for the ground state stacking, the interlayer binding is strong, yet the interlayer friction is small; (2) Li binds more strongly to the O-terminated monolayer, bilayer and heterostructure MXene systems when compared with the OHterminated MXenes due to the H+ induced repulsion to the Li atoms. The binding energy of Li decreases as the Li concentration increases due to enhanced repulsive interaction between the positively charged Li ions; (3) Ti2CO2/graphene and V2CO2/graphene heterostructures exhibit large Li atom binding energies making them the most promising candidates for battery applications. When fully loaded with Li atoms, the binding energy is -1.43 eV per Li atom and -1.78 eV per Li atom for Ti2CO2/graphene and V2CO2/graphene, respectively. These two heterostructures exhibit a nice compromise between storage capacity and kinetics. For example, the diffusion barrier of Li in Ti2CO2/graphene is around 0.3 eV which is comparable to that of graphite. Additionally, the calculated average voltages are 1.49 V and 1.93 V for Ti2CO2/graphene and V2CO2/graphene structures, respectively; (4) a small change in the in-plane lattice parameters (<1%), interatomic bond lengths and interlayer distances (<0.5 angstrom) proves the stability of the heterostructures against Li intercalation, and the impending phase separation into constituent layers and capacity fading during charge-discharge cycles in real battery applications; (5) as compared to bare M2CX2 bilayers, M2CX2/graphene heterostructures have lower molecular mass, offering high storage capacity; (6) the presence of graphene ensures good electrical conductivity that is essential for battery applications. Given these advantages, Ti2CO2/graphene and V2CO2/graphene heterostructures are predicted to be promising for lithium-ion battery applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000423981200049 Publication Date 2018-01-02
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.867 Times cited 131 Open Access
  Notes (down) ; This work was supported by the bilateral project between the Scientific and Technological Research Council of Turkey (TUBITAK) and FWO-Flanders, Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by the TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. We acknowledge the support from the TUBITAK (Grant No. 115F024 and 116F080). Part of this work was supported by the BAGEP Award of the Science Academy. ; Approved Most recent IF: 8.867
  Call Number UA @ lucian @ c:irua:149265UA @ admin @ c:irua:149265 Serial 4945
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Author Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D.
  Title Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 85 Issue 9 Pages 092502-092502,4
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000301183000002 Publication Date 2012-03-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 14 Open Access
  Notes (down) ; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:97180 Serial 1243
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Author Kosimov, D.P.; Dzhurakhalov, A.A.; Peeters, F.M.
  Title Carbon clusters: from ring structures to nanographene Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 19 Pages 195414,1-195414,12
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Integrated Molecular Plant Physiology Research (IMPRES); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The lowest-energy configurations of Cn(n≤55) clusters are obtained using the energy-minimization technique with the conjugate gradient method where a modified Brenner potential is invoked to describe the carbon and hydrocarbon interaction. We found that the ground-state configuration consists of a single ring for small number of C atoms and multiring structures are found with increasing n, which can be in planar, bowl-like or caplike form. Contrary to previous predictions, the binding energy Eb does not show even-odd oscillations and only small jumps are found in the Eb(n) curve as a consequence of specific types of edges or equivalently the number of secondary atoms. We found that hydrogenation of the edge atoms may change the ground-state configuration of the nanocluster. In both cases we determined the magic clusters. Special attention is paid to trigonal and hexagonal shaped carbon clusters and to clusters having a graphenelike configuration. Trigonal clusters are never the ground state while hexagonal-shaped clusters are only the ground state when they have zigzag edges.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000278142000103 Publication Date 2010-05-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 55 Open Access
  Notes (down) ; This work was supported by the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-V1). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:83385 Serial 278
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Author Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M.
  Title Metallic nanograins : spatially nonuniform pairing induced by quantum confinement Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 83 Issue 21 Pages 214509-214509,12
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract It is well known that the formation of discrete electron levels strongly influences the pairing in metallic nanograins. Here, we focus on another effect of quantum confinement in superconducting grains that was not studied previously, i.e., spatially nonuniform pairing. This effect is very significant when single-electron levels form bunches and/or a kind of shell structure. We find that, in highly symmetric grains, the order parameter can exhibit variations with position by an order of magnitude. Nonuniform pairing is closely related to a quantum-confinement-induced modification of the pairing-interaction matrix elements and size-dependent pinning of the chemical potential to groups of degenerate or nearly degenerate levels. For illustrative purposes, we consider spherical metallic nanograins and also rectangular shapes. We show that the relevant matrix elements are, as a rule, enhanced in the presence of quantum confinement, which favors spatial variations of the order parameter, compensating the corresponding energy cost. The size-dependent pinning of the chemical potential further increases the spatial variation of the pair condensate. The role of nonuniform pairing is smaller in less symmetric confining geometries and/or in the presence of disorder. However, it always remains of importance when the energy spacing between discrete electron levels δ is approaching the scale of the bulk gap ΔB, i.e., δ>0.10.2 ΔB.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000291310000006 Publication Date 2011-06-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 23 Open Access
  Notes (down) ; This work was supported by the Alexander von Humboldt Foundation, the Flemish Science Foundation (FWO-VI), and the Belgian Science Policy (IAP). M. D. C. acknowledges support of the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; Approved Most recent IF: 3.836; 2011 IF: 3.691
  Call Number UA @ lucian @ c:irua:90081 Serial 2010
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Author Chen, Y.; Shanenko, A.A.; Peeters, F.M.
  Title Vortex anomaly in low-dimensional fermionic condensates : quantum confinement breaks chirality Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 89 Issue 5 Pages 054513-54515
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Chiral fermions are responsible for low-temperature properties of vortices in fermionic condensates, both superconducting (charged) and superfluid (neutral). One of the most striking consequences of this fact is that the core of a single-quantum vortex collapses at low temperatures, T -> 0 (i.e., the Kramer-Pesch effect for superconductors), due to the presence of chiral quasiparticles in the vortex-core region. We show that the situation changes drastically for fermionic condensates confined in quasi-one-dimensional and quasi-two-dimensional geometries. Here quantum confinement breaks the chirality of in-core fermions. As a result, instead of the ultimate shrinking, the core of a single-quantum vortex extends at low temperatures, and the condensate profile surprisingly mimics the multiquantum vortex behavior. Our findings are relevant for nanoscale superconductors, such as recent metallic nanoislands on silicon, and also for ultracold superfluid Fermi gases in cigar-shaped and pancake-shaped atomic traps.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000332396800005 Publication Date 2014-02-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 5 Open Access
  Notes (down) ; This work was supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), the Methusalem Program, and the National Science Foundation of China under Grant No. NSFC-11304134. A. A. S. acknowledges the support of Brazilian agencies CNPq and FACEPE (Grant No. APQ-0589-1.05/08). ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:115822 Serial 3850
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Author Pogosov, W.V.; Misko, V.R.; Peeters, F.M.
  Title Geometry-induced localization of thermal fluctuations in ultrathin superconducting structures Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 82 Issue 5 Pages 054523-054523,6
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Thermal fluctuations of the order parameter in an ultrathin triangular-shaped superconducting structure are studied near Tc, in zero applied field. We find that the order parameter is prone to much larger fluctuations in the corners of the structure as compared to its interior. This geometry-induced localization of thermal fluctuations is attributed to the fact that condensate confinement in the corners is characterized by a lower effective dimensionality, which favors stronger fluctuations.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000281294700006 Publication Date 2010-08-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 2 Open Access
  Notes (down) ; This work was supported by the “Odysseus” Program of the Flemish government, FWO-Vl, and the Belgian Science Policy (IAP). W. V. P. acknowledges supports from the RFBR [Project No. 09-02-00248] and the “Dynasty Foundation.” ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:84470 Serial 1334
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Author Pogosov, W.V.; Zhao, H.J.; Misko, V.R.; Peeters, F.M.
  Title Kink-antikink vortex transfer in periodic-plus-random pinning potential : theoretical analysis and numerical experiments Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 2 Pages
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The influence of random pinning on the vortex dynamics in a periodic square potential under an external drive is investigated. Using numerical experiments and theoretical approach, we found several dynamical regimes of vortex motion that are different from the ones for a regular pinning potential. Vortex transfer is controlled by kinks and antikinks, which either pre-exist in the system or appear spontaneously in pairs and then propagate. When kinks and antikinks collide, they annihilate. We provide clear physical interpretations of the observed features.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000274002100087 Publication Date 2010-01-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 10 Open Access
  Notes (down) ; This work was supported by the “Odysseus” Program of the Flemish government, FWO-Vl, and IAP. W.V.P. acknowledges support from RFBR (Contract No. 09-02-00248). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:81251 Serial 1761
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Author Pogosov, W.V.; Misko, V.R.
  Title Vortex quantum tunneling versus thermal activation in ultrathin superconducting nanoislands Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 85 Issue 22 Pages 224508-224508,5
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We consider two possible mechanisms for single-vortex fluctuative entry/exit through the surface barrier in ultrathin superconducting disk-shaped nanoislands made of Pb and consisting of just a few monoatomic layers, which can be fabricated using modern techniques. We estimate tunneling probabilities and establish criteria for the crossover between these two mechanisms depending on magnetic field and system sizes. For the case of vortex entry, quantum tunneling dominates on the major part of the temperature/flux phase diagram. For the case of vortex exit, thermal activation turns out to be more probable. This nontrivial result is due to the subtle balance between the barrier height and width, which determine rates of the thermal activation and quantum tunneling, respectively.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000304856600003 Publication Date 2012-06-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 2 Open Access
  Notes (down) ; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). W. V. P. acknowledges numerous discussions with A. O. Sboychakov and the support from the Dynasty Foundation, the RFBR (Project No. 12-02-00339), and RFBR-CNRS programme (Project No. 12-02-91055). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:98908 Serial 3882
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Author Orlova, N.V.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M.; Vagov, A.V.; Axt, V.M.
  Title Ginzburg-Landau theory for multiband superconductors : microscopic derivation Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 13 Pages 134510-134518
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract A procedure to derive the Ginzburg-Landau (GL) theory from the multiband BCS Hamiltonian is developed in a general case with an arbitrary number of bands and arbitrary interaction matrix. It combines the standard Gor'kov truncation and a subsequent reconstruction in order to match accuracies of the obtained terms. This reconstruction recovers the phenomenological GL theory as obtained from the Landau model of phase transitions but offers explicit microscopic expressions for the relevant parameters. Detailed calculations are presented for a three-band system treated as a prototype multiband superconductor. It is demonstrated that the symmetry in the coupling matrix may lead to the chiral ground state with the phase frustration, typical for systems with broken time-reversal symmetry. DOI: 10.1103/PhysRevB.87.134510
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000317586700002 Publication Date 2013-04-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 57 Open Access
  Notes (down) ; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). A.A.S. acknowledges useful discussions with D. Neilson. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:108464 Serial 1344
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Author Misko, V.R.; Bothner, D.; Kemmler, M.; Kleiner, R.; Koelle, D.; Peeters, F.M.; Nori, F.
  Title Enhancing the critical current in quasiperiodic pinning arrays below and above the matching magnetic flux Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 82 Issue 18 Pages 184512-184512,7
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Quasiperiodic pinning arrays, as recently demonstrated theoretically and experimentally using a fivefold Penrose tiling, can lead to a significant enhancement of the critical current Ic as compared to traditional regular pinning arrays. However, while regular arrays showed only a sharp peak in Ic(Φ) at the matching flux Φ1 and quasiperiodic arrays provided a much broader maximum at Φ<Φ1, both types of pinning arrays turned out to be inefficient for fluxes larger than Φ1. We demonstrate theoretically and experimentally the enhancement of Ic(Φ) for Φ>Φ1 by using non-Penrose quasiperiodic pinning arrays. This result is based on a qualitatively different mechanism of flux pinning by quasiperiodic pinning arrays and could be potentially useful for applications in superconducting microelectronic devices operating in a broad range of magnetic fields.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000283923400006 Publication Date 2010-11-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 33 Open Access
  Notes (down) ; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, the FWO-Vl, and by the DFG via SFB/TRR21. V. R. M. is grateful to the FWO-Vl for the support of the research stay at the DML (ASI, RIKEN), and to F. N. for hospitality. M. K. gratefully acknowledges support from the Carl-Zeiss-Stiftung, and D. B. from the Evangelisches Studienwerk e.V. Villigst. F. N. acknowledges partial support from the Laboratory of Physical Sciences, National Security Agency, Army Research Office, DARPA, AFOSR, National Science Foundation under Grant No. 0726909, JSPS-RFBR under Contract No. 09-02-92114, Grant-in-Aid for Scientific Research (S), MEXT Kakenhi on Quantum Cybernetics, and Funding Program for Innovative R&D on S&T (FIRST). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:85800 Serial 1066
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Author Lin, N.S.; Misko, V.R.; Peeters, F.M.
  Title Dynamics of multishell vortex structures in mesoscopic superconducting Corbino disks Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 13 Pages 134504,1-134504,11
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We study the dynamics of vortex shells in mesoscopic superconducting Corbino disks, where vortices form shells as recently observed in micrometer-sized Nb disks. Due to the interplay between the vortex-vortex interaction, the gradient Lorentz force and the (in)commensurability between the numbers of vortices in shells, the process of angular melting of vortex-shell configurations becomes complex. Angular melting can start either from the center of the disk (where the shear stress is maximum) or from its boundary (where the shear stress is minimum) depending on the specific vortex configuration. Furthermore, we found that two kinds of defects can exist in such vortex-shell structures: intrashell and intershell defects. An intrashell defect may lead to an inverse dynamic behavior, i.e., one of the vortex shells under a stronger driving force can rotate slower than the adjacent shell that is driven by a weaker Lorentz force. An intershell defect always locks more than two shells until the gradient of the Lorentz force becomes large enough to break the rigid-body rotation of the locked shells. Such a lock-unlock process leads to hysteresis in the angular velocities of the shells.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000277207900079 Publication Date 2010-04-02
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 11 Open Access
  Notes (down) ; This work was supported by the “Odysseus” program of the Flemish Government and the Flemish Science Foundation (FWO-V1), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-V1. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:82803 Serial 779
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Author Nowak, M.P.; Szafran, B.; Peeters, F.M.
  Title Fano resonances and electron spin transport through a two-dimensional spin-orbit-coupled quantum ring Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 84 Issue 23 Pages 235319-235319,8
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Electron transport through a spin-orbit-coupled quantum ring is investigated within linear response theory. We show that the finite width of the ring results in the appearance of Fano resonances in the conductance. This turns out to be a consequence of the spin-orbit interaction that leads to a breaking of the parity of the states localized in the ring. The resonances appear when the system is close to maxima of Aharonov-Casher conductance oscillations where spin transfer is heavily modified. When the spin-orbit coupling strength is detuned from the Aharonov-Casher maxima the resonances are broadened resulting in a dependence of the spin transport on the electron Fermi energy in contrast to predictions from one-dimensional models.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000298605700002 Publication Date 2011-12-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 19 Open Access
  Notes (down) ; This work was supported by the “Krakow Interdisciplinary PhD Project in Nanoscience and Advanced Nanostructures” operated within the Foundation for Polish Science MPD Programme cofinanced by the EU European Regional Development Fund, Project No. N N202103938 supported by the Ministry of Science and Higher Education (MNiSW) for 2010-2013, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). This research was supported in part by PL-Grid Infrastructure. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
  Call Number UA @ lucian @ c:irua:94292 Serial 1171
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Author Bacaksiz, C.; Yagmurcukardes, M.; Peeters, F.M.; Milošević, M.V.
  Title Hematite at its thinnest limit Type A1 Journal article
  Year 2020 Publication 2d Materials Abbreviated Journal 2D Mater
  Volume 7 Issue 2 Pages 025029
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Motivated by the recent synthesis of two-dimensional alpha-Fe2O3 (Balan et al 2018 Nat. Nanotechnol. 13 602), we analyze the structural, vibrational, electronic and magnetic properties of single- and few-layer alpha-Fe2O3 compared to bulk, by ab initio and Monte-Carlo simulations. We reveal how monolayer alpha-Fe2O3 (hematene) can be distinguished from the few-layer structures, and how they all differ from bulk through observable Raman spectra. The optical spectra exhibit gradual shift of the prominent peak to higher energy, as well as additional features at lower energy when alpha-Fe2O3 is thinned down to a monolayer. Both optical and electronic properties have strong spin asymmetry, meaning that lower-energy optical and electronic activities are allowed for the single-spin state. Finally, our considerations of magnetic properties reveal that 2D hematite has anti-ferromagnetic ground state for all thicknesses, but the critical temperature for Morin transition increases with decreasing sample thickness. On all accounts, the link to available experimental data is made, and further measurements are prompted.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000537341000002 Publication Date 2020-01-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 5.5 Times cited 12 Open Access
  Notes (down) ; This work was supported by Research Foundation-Flanders (FWO-Vlaanderen). Computational resources were provided by Flemish Supercomputer Center(VSC), and TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). Part of this work was also supported by FLAG-ERA project TRANS-2D-TMD and TOPBOF-UAntwerp. MY was supported by a postdoctoral fellowship from the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 5.5; 2020 IF: 6.937
  Call Number UA @ admin @ c:irua:170301 Serial 6533
Permanent link to this record
 

 
Author Liu, Y.; Cheng, F.; Li, X.J.; Peeters, F.M.; Chang, K.
  Title Tuning of the two electron states in quantum rings through the spin-orbit interaction Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 82 Issue 4 Pages 1-7
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The effect of the Coulomb interaction on the energy spectrum and anisotropic distribution of two electron states in a quantum ring in the presence of Rashba spin-orbit interaction (RSOI) and Dresselhaus SOI (DSOI) is investigated in the presence of a perpendicular magnetic field. We find that the interplay between the RSOI and DSOI makes the single quantum ring behaves like a laterally coupled quantum dot and the interdot coupling can be tuned by changing the strengths of the SOIs. The interplay can lead to singlet-triplet state mixing and anticrossing behavior when the singlet and triplet states meet with increasing magnetic field. The two electron ground state displays a bar-bell-like spatial anisotropic distribution in a quantum ring at a specific crystallographic direction, i.e., [110] or [11̅ 0], which can be switched by reversing the direction of the perpendicular electric field. The ground state exhibits a singlet-triplet state transition with increasing magnetic field and strengths of RSOI and DSOI. An anisotropic electron distribution is predicted which can be detected through the measurement of its optical properties.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000280234100006 Publication Date 2010-07-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 14 Open Access
  Notes (down) ; This work was supported by NSFC under Grants No. 60525405 and No. 10874175 and the Belgium Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:84087 Serial 3756
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Author Zha, G.-Q.; Covaci, L.; Peeters, F.M.; Zhou, S.-P.
  Title Majorana zero-energy modes and spin current evolution in mesoscopic superconducting loop systems with spin-orbit interaction Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 92 Issue 92 Pages 094516
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The Majorana zero modes and persistent spin current in mesoscopic d-wave-superconducting loops with spin-orbit (SO) interaction are investigated by numerically solving the spin-generalized Bogoliubov-de Gennes equations self-consistently. For some appropriate strength of the SO coupling, Majorana zero-energy states and sharp jumps of the spin-polarized currents can be observed when the highest energy levels cross the Fermi energy in the spectrum, leading to spin currents with opposite chirality flowing near the inner and outer edges of the sample. When the threaded magnetic flux turns on, four flux-dependent patterns of the persistent spin current with step-like features show up, accompanied by Majorana edge modes at flux values where the energy gap closes. Moreover, the Majorana zero mode is highly influenced by the direction of the Zeeman field. A finite in-plane field can lead to the gap opening since the inversion symmetry is broken. Remarkably, multiple Majorana zero-energy states occur in the presence of an out-of-plane field h(z), and the number of steps in the spin current evolution can be effectively tuned by the field strength due to the shift of Majorana zero modes. Finally, when the loop sample contains surface indentation defects, zero-energy modes can always show up in the presence of an appropriate h(z). Interestingly, multiple Majorana states may be present in the system with a corner defect even if h(z) = 0.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000362081000002 Publication Date 2015-09-30
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 11 Open Access
  Notes (down) ; This work was supported by National Natural Science Foundation of China under Grants No. 61371020, No. 61271163, and No. 61571277, by the Visiting Scholar Program of Shanghai Municipal Education Commission, and by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
  Call Number UA @ lucian @ c:irua:132467 Serial 4203
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Author Zha, G.-Q.; Covaci, L.; Peeters, F.M.; Zhou, S.-P.
  Title Majorana fermion states and fractional flux periodicity in mesoscopic d-wave superconducting loops with spin-orbit interaction Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 1 Pages 014522
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We numerically investigate the spin-orbit (SO) coupling effect on the magnetic flux evolution of energy and supercurrent in mesoscopic d-wave superconducting loops by solving the spin-generalized Bogoliubov-de Gennes equations self-consistently. It is found that the energy spectrum splits when the SO interaction is involved and the Majorana zero mode can be realized in the [100] edges of square systems for an appropriate SO coupling strength. Superconducting phase transitions appear when the energy gap closes, accompanied by energy jumps between different energy parabolas in the ground state, which provides a possible mechanism to support fractional flux periodicity of supercurrent. Moreover, in the case of rectangular loops with SO coupling, the jumps of the ground-state energy gradually disappear by increasing the ratio of length to height of the sample, and a paramagnetic response with opposite direction of the screening current around zero flux value can occur in such systems.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000341233800010 Publication Date 2014-07-31
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 7 Open Access
  Notes (down) ; This work was supported by National Natural Science Foundation of China under Grants No. 61371020 and No. 61271163, by Visiting Scholar Program of Shanghai Municipal Education Commission, by Innovation Program of Shanghai Municipal Education Commission under Grant No. 13YZ006, and by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:119266 Serial 1938
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Author Zhao, Z.X.; Ma, X.; Cao, S.; Li, Y.Y.; Zeng, C.Y.; Wang, D.X.; Yao, X.; Deng, Z.J.; Zhang, X.P.
  Title Identification of nano-width variants in a fully monoclinic martensitic Ni50Ti50 alloy by scanning electron microscope-based transmission Kikuchi diffraction and improved groupoid structure approach Type A1 Journal article
  Year 2020 Publication Materials Letters Abbreviated Journal Mater Lett
  Volume 281 Issue Pages 128624
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Nano-width martensite plates in a fully martensitic Ni50Ti50 alloy are indexed successfully by using the off-axis transmission Kikuchi diffraction in scanning electron microscope (i.e., SEM-based TKD). The data obtained by SEM-TKD are effectively interpreted using an improved approach based on the framework of the theoretical groupoid structure method, where the equivalent variants transformed from the monoclinic variants are introduced to calculate all theoretical axis/angle pairs of rotation, and to formulate a complete list of source martensite to target martensite pairs. Consequently, B19' monoclinic martensite variants in NiTi alloys are identified unambiguously, by using numerical comparison between the experimental and theoretical rotation components, without the reference of retained parent phase. (C) 2020 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000581134200033 Publication Date 2020-09-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0167-577x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3 Times cited Open Access Not_Open_Access
  Notes (down) ; This work was supported by National Natural Science Foundation of China under Grant Nos. 51571092 and 51401081, and Guangdong Provincial Natural Science Foundation under Grant Nos. 2018B0303110012 and 2017A030313323. ; Approved Most recent IF: 3; 2020 IF: 2.572
  Call Number UA @ admin @ c:irua:173509 Serial 6540
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Author Wei, P.; Ke, B.; Xing, L.; Li, C.; Ma, S.; Nie, X.; Zhu, W.; Sang, X.; Zhang, Q.; Van Tendeloo, G.; Zhao, W.
  Title Atomic-resolution interfacial structures and diffusion kinetics in Gd/Bi0.5Sb1.5Te3 magnetocaloric/thermoelectric composites Type A1 Journal article
  Year 2020 Publication Materials Characterization Abbreviated Journal Mater Charact
  Volume 163 Issue Pages 110240-110248
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The demand of a full solid-state cooling technology based on magnetocaloric and thermoelectric effects has led to a growing interest in screening candidate materials with high-efficiency cooling performance, which also stimulates the exploration of magnetocaloric/thermoelectric hybrid cooling materials. A series of Gd/Bi0.5Sb1.5Te3 composites was fabricated in order to develop the hybrid cooling technology. The chemical composition, phase structure and diffusion kinetics across the reaction layers in Gd/Bi0.5Sb1.5Te3 composites were analyzed at different reaction temperatures. Micro-area elemental analysis indicates that the formation of interfacial phases is dominated by the diffusion of Gd and Te while the diffusion of Bi and Sb is impeded. The interfacial phases, including GdTe2, GdTe3, and intermediate phases GdTex, are identified by atomic-resolution electron microscopy. The concentration modulation of Gd and Te is adapted by altering the stacking of the Te square-net sheets and the corrugated GdTe sheets. Boltzmann-Marano analysis was applied to reveal the diffusion kinetics of Gd and Te in the interfacial layers. The diffusion coefficients of Te in GdTe2 and GdTe3 are much higher than that of Gd while in GdTe the situation is reversed. This study provides a clear picture to understand the interfacial phase structures down to an atomic scale as well as the interfacial diffusion kinetics in Gd/Bi0.5Sb1.5Te3 hybrid cooling materials.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000551341700045 Publication Date 2020-03-03
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1044-5803 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.7 Times cited 1 Open Access Not_Open_Access
  Notes (down) ; This work was supported by National Natural Science Foundation of China (Nos. 91963122, 11834012, 51620105014, 51521001, 51902237), National Key Research and Development Program of China (No. 2018YFB0703603), the Fundamental Research Funds for the Central Universities (WUT: 2019III012GX, 183101006). XRD and EPMA experiments were performed at the Center for Materials Research and Testing of Wuhan University of Technology. ; Approved Most recent IF: 4.7; 2020 IF: 2.714
  Call Number UA @ admin @ c:irua:171317 Serial 6456
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Author Wu, S.-M.; Liu, X.-L.; Lian, X.-L.; Tian, G.; Janiak, C.; Zhang, Y.-X.; Lu, Y.; Yu, H.-Z.; Hu, J.; Wei, H.; Zhao, H.; Chang, G.-G.; Van Tendeloo, G.; Wang, L.-Y.; Yang, X.-Y.; Su, B.-L.
  Title Homojunction of oxygen and titanium vacancies and its interfacial n-p effect Type A1 Journal article
  Year 2018 Publication Advanced materials Abbreviated Journal Adv Mater
  Volume 30 Issue 32 Pages 1802173
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The homojunction of oxygen/metal vacancies and its interfacial n-p effect on the physiochemical properties are rarely reported. Interfacial n-p homojunctions of TiO2 are fabricated by directly decorating interfacial p-type titanium-defected TiO2 around n-type oxygen-defected TiO2 nanocrystals in amorphous-anatase homogeneous nanostructures. Experimental measurements and theoretical calculations on the cell lattice parameters show that the homojunction of oxygen and titanium vacancies changes the charge density of TiO2; a strong EPR signal caused by oxygen vacancies and an unreported strong titanium vacancies signal of 2D H-1 TQ-SQ MAS NMR are present. Amorphous-anatase TiO2 shows significant performance regarding the photogeneration current, photocatalysis, and energy storage, owing to interfacial n-type to p-type conductivity with high charge mobility and less structural confinement of amorphous clusters. A new homojunction of oxygen and titanium vacancies concept, characteristics, and mechanism are proposed at an atomic-/nanoscale to clarify the generation of oxygen vacancies and titanium vacancies as well as the interface electron transfer.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos 000440813300022 Publication Date 2018-06-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 19.791 Times cited 39 Open Access Not_Open_Access
  Notes (down) ; This work was supported by National Key R&D Program of China (2017YFC1103800), National SFC (U1662134, U1663225, 51472190, 51611530672, 21711530705, 51503166, 21706199), ISTCP (2015DFE52870), PCSIRT (IRT_15R52), HPNSF (2016CFA033, 2017CFB487), and SKLPPC (PPC2016007). ; Approved Most recent IF: 19.791
  Call Number UA @ lucian @ c:irua:153106 Serial 5105
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Author Van Tendeloo, L.; Wangermez, W.; Vandekerkhove, A.; Willhammar, T.; Bals, S.; Maes, A.; Martens, J.A.; Kirschhock, C.E.A.; Breynaert, E.
  Title Postsynthetic high-alumina zeolite crystal engineering in organic free hyper-alkaline media Type A1 Journal article
  Year 2017 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 29 Issue 29 Pages 629-638
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Postsynthetic modification of high -alumina zeolites in hyper alkaline media can be tailored toward alteration of framework topology, crystal size and morphology, or desired Si/A1 ratio. FAU, EMT, MAZ, KFI, HEU, and LTA starting materials were treated with 1.2 M MOH (M = Na, K, RE, or Cs), leading to systematic ordered porosity or fully transformed frameworks with new topology and adjustable Si/Al ratio. In addition to the versatility of this tool for zeolite crystal engineering, these alterations improve understanding of the crystal chemistry. Such knowledge can guide further development in zeolite crystal engineering. Postsynthetic alteration also provides insight on the long-term stability of aluminosilicate zeolites that are used as a sorption sink in concrete -based waste disposal facilities in harsh alkaline conditions.
  Address
  Corporate Author Thesis
  Publisher American Chemical Society Place of Publication Washington, D.C Editor
  Language Wos 000392891700021 Publication Date 2016-12-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 16 Open Access OpenAccess
  Notes (down) ; This work was supported by long-term structural funding by the Flemish Government (Methusalem grant of Prof. J. Martens) and by ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Fissile Materials, as part of the program on surface disposal of Belgian Category A waste. The Belgian government is acknowledged for financing the interuniversity poles of attraction (IAP-PAI). S.B. acknowledges financial support from European Research Council (ERC Advanced Grant No. 24691-COUNTATOMS, ERC Starting Grant No. 335078-COLOURATOMS). ; Ecas_Sara Approved Most recent IF: 9.466
  Call Number UA @ lucian @ c:irua:152674UA @ admin @ c:irua:152674 Serial 5145
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Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
  Title Extra Dirac points in the energy spectrum for superlattices on single-layer graphene Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 81 Issue 7 Pages 075438,1-075438,7
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the emergence of extra Dirac points in the electronic structure of a periodically spaced barrier system, i.e., a superlattice, on single-layer graphene, using a Dirac-type Hamiltonian. Using square barriers allows us to find analytic expressions for the occurrence and location of these new Dirac points in k space and for the renormalization of the electron velocity near them in the low-energy range. In the general case of unequal barrier and well widths the new Dirac points move away from the Fermi level and for given heights of the potential barriers there is a minimum and maximum barrier width outside of which the new Dirac points disappear. The effect of these extra Dirac points on the density of states and on the conductivity is investigated.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000274998200133 Publication Date 2010-02-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 211 Open Access
  Notes (down) ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the Brazilian Council for Research (CNPq), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:81767 Serial 1159
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Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
  Title Kronig-Penney model on bilayer graphene : spectrum and transmission periodic in the strength of the barriers Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 82 Issue 23 Pages 235408-235408,10
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We show that the transmission through single and double δ-function potential barriers of strength P=VWb/ℏvF in bilayer graphene is periodic in P with period π. For a certain range of P values we find states that are bound to the potential barrier and that run along the potential barrier. Similar periodic behavior is found for the conductance. The spectrum of a periodic succession of δ-function barriers (Kronig-Penney model) in bilayer graphene is periodic in P with period 2π. For P smaller than a critical value Pc, the spectrum exhibits two Dirac points while for P larger than Pc an energy gap opens. These results are extended to the case of a superlattice of δ-function barriers with P alternating in sign between successive barriers; the corresponding spectrum is periodic in P with period π.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000286766900008 Publication Date 2010-12-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 34 Open Access
  Notes (down) ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the Canadian NSERC under Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
  Call Number UA @ lucian @ c:irua:88910 Serial 1768
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Author Saniz, R.; Partoens, B.; Peeters, F.M.
  Title Green function approach to superconductivity in nanowires Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 85 Issue 14 Pages 144504-144504,7
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Superconductivity in nanowires made of weak coupling superconductor materials is investigated using a Green function approach. We show that these are multigap systems in which the ratio Delta(T)/k(B)T(c) is to a large extent similar to what is observed in some high-T-c two-gap systems, such as MgB2 and some of the Fe-based superconductors. On the other hand, because of confinement, the superfluid density has a temperature behavior of the form n(s)(T) = 1 – (T/T-c)(3) near T-c, thus deviating from the BCS behavior for bulk superconductors.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000302290700006 Publication Date 2012-04-03
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 1 Open Access
  Notes (down) ; This work was supported by FWO-Vl and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:97764 Serial 1381
Permanent link to this record
 

 
Author Nga, T.T.N.; Peeters, F.M.
  Title Influence of electron-electron interaction on the cyclotron resonance spectrum of magnetic quantum dots containing few electrons Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 83 Issue 7 Pages 075419-075419,6
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The configuration interaction method is used to obtain the magneto-optical absorption spectrum of a few-electron (Ne=1,2,,5) quantum dot containing a single magnetic ion. We find that the IR spectrum (the position, the number, and the oscillator strength of the cyclotron resonance peaks) depends on the strength of the Coulomb interaction, the number of electrons, and the position of the magnetic ion. We find that the Kohn theorem is no longer valid as a consequence of the electron-spin-magnetic-ion-spin-exchange interaction.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000287584600011 Publication Date 2011-02-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 8 Open Access
  Notes (down) ; This work was supported by FWO-Vl (Flemish Science Foundation), the Brazilian science foundation CNPq, and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2011 IF: 3.691
  Call Number UA @ lucian @ c:irua:88912 Serial 1620
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Author Nowak, M.P.; Szafran, B.; Peeters, F.M.
  Title Resonant harmonic generation and collective spin rotations in electrically driven quantum dots Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 86 Issue 12 Pages 125428
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Spin rotations induced by an ac electric field in a two-electron double quantum dot are studied by an exact numerical solution of the time-dependent Schrodinger equation in the context of recent electric-dipole spin resonance experiments on gated nanowires. We demonstrate that the splitting of the main resonance line by the spin exchange coupling is accompanied by the appearance of fractional resonances and that both these effects are triggered by interdot tunnel coupling. We find that the ac-driven system generates residual but distinct harmonics of the driving frequency, which are amplified when tuned to the main transition frequency. The mechanism is universal for electron systems in electrically driven potentials and works also in the absence of electron-electron interaction or spin-orbit coupling.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000308867300005 Publication Date 2012-09-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 29 Open Access
  Notes (down) ; This work was supported by funds of the Ministry of Science and Higher Education (MNiSW) for 2012-2013 under Project No. IP2011038671, and by PL-Grid Infrastructure. M.P.N. gratefully acknowledges support from the Foundation for Polish Science (FNP) under START and MPD program cofinanced by the EU European Regional Development Fund. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:101839 Serial 2885
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Author Berdiyorov, G.; Harrabi, K.; Oktasendra, F.; Gasmi, K.; Mansour, A.I.; Maneval, J.P.; Peeters, F.M.
  Title Dynamics of current-driven phase-slip centers in superconducting strips Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 5 Pages 054506
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Phase-slip centers/lines and hot spots are the main mechanisms for dissipation in current-carrying superconducting thin films. The pulsed-current method has recently been shown to be an effective tool in studying the dynamics of phase-slip centers and their evolution to hot spots. We use the time-dependent Ginzburg-Landau theory in the study of the dynamics of the superconducting condensate in superconducting strips under external current and zero external magnetic field. We show that both the flux-flow state (i.e., slow-moving vortices) and the phase-slip line state (i.e., fast-moving vortices) are dynamically stable dissipative units with temperature smaller than the critical one, whereas hot spots, which are localized normal regions where the local temperature exceeds the critical value, expand in time, resulting ultimately in a complete destruction of the condensate. The response time of the system to abrupt switching on of the overcritical current decreases with increasing both the value of the current (at all temperatures) and temperature (for a given value of the applied current). Our results are in good qualitative agreement with experiments we have conducted on Nb thin strips.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000344656700003 Publication Date 2014-08-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 42 Open Access
  Notes (down) ; This work was supported by EU Marie Curie Project No. 253057, the Flemish Science Foundation (FWO-Vl), and King Fahd University of Petroleum and Minerals, Saudi Arabia, under the IN131034 DSR project. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:121229 Serial 775
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Author D'Olieslaeger, L.; Pfannmöller, M.; Fron, E.; Cardinaletti, I.; Van der Auweraer, M.; Van Tendeloo, G.; Bals, S.; Maes, W.; Vanderzande, D.; Manca, J.; Ethirajan, A.
  Title Tuning of PCDTBT : PC71BM blend nanoparticles for eco-friendly processing of polymer solar cells Type A1 Journal article
  Year 2017 Publication Solar energy materials and solar cells Abbreviated Journal Sol Energ Mat Sol C
  Volume 159 Issue 159 Pages 179-188
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract We report the controlled preparation of water processable nanoparticles (NPs) employing the push-pull polymer PCDTBT and the fullerene acceptor PC71BM in order to enable solar cell processing using eco-friendly solvent (i.e. water). The presented method provides the possibility to separate the formation of the active layer blend and the deposition of the active layer into two different processes. For the first time, the benefits of aqueous processability for the high-potential class of push-pull polymers, generally requiring high boiling solvents, are made accessible. With our method we demonstrate excellent control over the blend stoichiometry and efficient mixing. Furthermore, we provide visualization of the nano morphology of the different NPs to obtain structural information down to similar to 2 nm resolution using advanced analytical electron microscopy. The imaging directly reveals very small compositional demixing in the PCDTBT:PC71BM blend NPs, in the size range of about <5 nm, indicating fine mixing at the molecular level. The suitability of the proposed methodology and materials towards the aspects of eco-friendly processing of organic solar cells is demonstrated through a processing of lab scale NPs solar cell prototypes reaching a power conversion efficiency of 1.9%. (C) 2016 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos 000388053600021 Publication Date 2016-09-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0927-0248 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.784 Times cited 32 Open Access OpenAccess
  Notes (down) ; This work was supported by BOF funding of Hasselt University, the Interreg project Organext, and the IAP 7/05 project FS2 (Functional Supramolecular Systems), granted by the Science Policy Office of the Belgian Federal Government (BELSPO). A.E. is a post-doctoral fellow of the Flanders Research Foundation (FWO). M.P. gratefully acknowledges the SIM NanoForce program for financial support. S.B. further acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). The authors are thankful for technical support by J. Smits, T. Vangerven, and J. Baccus. ; ecas_sara Approved Most recent IF: 4.784
  Call Number UA @ lucian @ c:irua:139157UA @ admin @ c:irua:139157 Serial 4450
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Author Rouchon, V.; Pellizzi, E.; Janssens, K.
  Title FTIR techniques applied to the detection of gelatine in paper artifacts: from macroscopic to microscopic approach Type A1 Journal article
  Year 2010 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
  Volume 100 Issue 3 Pages 663-669
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract In order to render paper hydrophobic for ink and thus adequate for writing, gelatine has been largely used. To this day, it is still employed in conservation workshops as an adhesive or a sizing agent, for instance, during the treatment of iron gall ink manuscripts. Various types and concentrations of gelatine are recommended, depending on the desired effect, but little information is available regarding to the physical distribution of gelatine in the paper. This aspect is however determinant for a better control of conservation treatments. In this work, we investigate the possibilities offered by FTIR microscopy for the measurement of the gelatine distribution in paper. Laboratory papers were preliminary treated with different types of gelatine and then embedded in a resin and cut in thin slices. Mapping techniques enable to compare the penetration of different types of gelatine in a semiquantitative way. The performance of conventional laboratory equipment and synchrotron radiation experimental setup are discussed.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000281317700011 Publication Date 2010-04-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.455 Times cited 12 Open Access
  Notes (down) ; This work was performed with the support of the Fondazione Cassa di Risparmio di Torino, who founded the postgraduate internship of Eleonora Pellizzi at the CRCC (Master dei talenti). It received the technical support of the SMIS line of the SOLEIL synchrotron (Saint Aubin, France). We are thankful to all our colleagues who helped us during our experiments: Anne Laurence Dupont for providing gelatine samples, Chakib Djediat (Museum National d'Histoire Naturelle, Paris) for his advice regarding the samples preparation, Christophe Sandt (Synchrotron SOLEIL) for his help and availability during our Beam time allocation, and Paul Dumas (Synchrotron SOLEIL) for his warm reception on the SMIS line. ; Approved Most recent IF: 1.455; 2010 IF: 1.765
  Call Number UA @ admin @ c:irua:84579 Serial 5627
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Author Dimitrievska, M.; Shea, P.; Kweon, K.E.; Bercx, M.; Varley, J.B.; Tang, W.S.; Skripov, A.V.; Stavila, V.; Udovic, T.J.; Wood, B.C.
  Title Carbon Incorporation and Anion Dynamics as Synergistic Drivers for Ultrafast Diffusion in Superionic LiCB11H12 and NaCB11H12 Type A1 Journal article
  Year 2018 Publication Advanced energy materials Abbreviated Journal Adv Energy Mater
  Volume 8 Issue 15 Pages 1703422
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The disordered phases of LiCB11H12 and NaCB11H12 possess superb superionic conductivities that make them suitable as solid electrolytes. In these materials, cation diffusion correlates with high orientational mobilities of the CB11H12- anions; however, the precise relationship has yet to be demonstrated. In this work, ab initio molecular dynamics and quasielastic neutron scattering are combined to probe anion reorientations and their mechanistic connection to cation mobility over a range of timescales and temperatures. It is found that anions do not rotate freely, but rather transition rapidly between orientations defined by the cation sublattice symmetry. The symmetry-breaking carbon atom in CB11H12- also plays a critical role by perturbing the energy landscape along the instantaneous orientation of the anion dipole, which couples fluctuations in the cation probability density directly to the anion motion. Anion reorientation rates exceed 3 x 10(10) s(-1), suggesting the underlying energy landscape fluctuates dynamically on diffusion-relevant timescales. Furthermore, carbon is found to modify the orientational preferences of the anions and aid rotational mobility, creating additional symmetry incompatibilities that inhibit ordering. The results suggest that synergy between the anion reorientational dynamics and the carbon-modified cation-anion interaction accounts for the higher ionic conductivity in CB11H12- salts compared with B12H122-.
  Address
  Corporate Author Thesis
  Publisher WILEY-VCH Verlag GmbH & Co. Place of Publication Weinheim Editor
  Language Wos 000434031400026 Publication Date 2018-02-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1614-6832; 1614-6840 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 16.721 Times cited 20 Open Access OpenAccess
  Notes (down) ; This work was performed in part under the auspices of the U.S. Department of Energy at Lawrence Livermore National Laboratory (LLNL) under Contract No. DE-AC52-07NA27344 and funded by Laboratory Directed Research and Development Grant 15-ERD-022. Computing support came from the LLNL Institutional Computing Grand Challenge program. This work was also performed in part within the assignment of the Russian Federal Agency of Scientific Organizations (program “Spin” No. 01201463330). The authors gratefully acknowledge support from the Russian Foundation for Basic Research under Grant No. 15-03-01114 and the Ural Branch of the Russian Academy of Sciences under Grant No. 15-9-2-9. A.V.S. gratefully acknowledges travel support from CRDF Global in conjunction with this work under Grant No. FSCX-15-61826-0. M.D. gratefully acknowledges research support from the Hydrogen Materials-Advanced Research Consortium (HyMARC), established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Fuel Cell Technologies Office, under Contract No. DE-AC36-08GO28308. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy National Nuclear Security Administration under Contract No. DE-AC04-94AL85000. This work utilized facilities supported in part by the National Science Foundation under Agreement No. DMR-1508249. The views, opinions, findings, and conclusions stated herein are those of the authors and do not necessarily reflect those of CRDF Global, or the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. ; Approved Most recent IF: 16.721
  Call Number UA @ lucian @ c:irua:152045 Serial 5015
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